As is generally the case when Apple keeps the housing of a product the same, the new iPad has changed a lot under the hood. But the differences all need to be experienced up close; if you’re five feet away from both devices’ screens, you mightn’t even notice that anything’s different. The third-generation iPad launched with the same iOS 5.1 operating system that was released a week earlier for the iPad and iPad 2, retains the same fonts, icons, backgrounds, and apps, plays the same games, and displays the same web pages. What’s new, of course, is four times the visual detail in almost everything that appears on screen. Take note of the word “almost.”

Apple did something crazy with the new iPad’s display: rather than taking the modest iterative approach that numerous companies—historically including Apple, particularly in past iPods—have adopted for second- or third-generation devices, the new iPad has rapidly achieved a quantum and once unthinkable leap in display technology. Rather than shifting to a 16:9 or 16:10 aspect ratio with fewer pixels than a premium HDTV—a formula Apple has used over the years for almost all of its more expensive MacBooks—the company instead retained the past iPads’ 4:3 aspect ratio and quadrupled the pixel count to surpass the resolutions of HDTVs. As was noted during its introduction, the new iPad’s 2048x1536 screen actually has 3.1 million pixels, or 1 million pixels more than the best HDTV in your house. Only Apple’s most expensive iMacs and standalone monitors offer higher resolutions, and then, they’re 27” on the diagonal and weigh between 23 and 31 pounds.

There are numerous ways to quantify the new iPad’s resolution, but it suffices to say that the screen can display more detail than the rear screen on any digital camera, phone, digital media player, or even every MacBook computer—including the current top-of-the-line MacBook Pro, which sells for $2,500 and peaks at an HDTV-like 1920x1200 pixels. The new iPad’s screen has a pixel density of 264 pixels per inch, higher than any Apple device save the most recent iPhones and iPod touch. Apple and its suppliers deserve considerable credit for undertaking the engineering and manufacturing feats necessary to bring such a high-resolution screen to market; its suppliers are responsible for manufacturing the parts, but Apple certainly helped encourage early mass production with substantial, forward-thinking investments. Moreover, every one of the seven new iPads we tested had a pixel-perfect display, with no stuck or dead pixels. Apart from Apple, this sort of quality control for a new and previously unthinkable high-definition screen is all but unheard of— and yet, it’s here at the same price points as last year’s iPads.

Given what it has achieved in resolution, it was somewhat surprising that Apple hasn’t attempted to otherwise quantify the screen’s performance beyond a claimed 44% greater color saturation than its predecessor. It hasn’t promised a greater number of colors, superior contrast, greater color accuracy, or better brightness. Having tested the latest MacBook Air models, which display markedly less accurate colors than the MacBook Pro—enough to make professionally shot photographs look like blotchy messes—we were concerned.

There’s good news and bad news here. Judged solely on color, the third-generation iPad’s screen (above, right) is better overall than its predecessor (above, left). At peak brightness, the new iPad’s renditions of photos and videos look extremely similar to Apple’s high-resolution iMac and Thunderbolt Displays, with noticeably richer—and generally more accurate—colors than prior iPads. However, not all new iPad screens are created exactly equal, as shown in the picture below. Some models ship with a screen that tends to emphasize yellows, improving everything except for skin tones, while others are more neutrally balanced, variations we’ve seen in past iPod touches and iPhones due to different screen producers. As in the past, there’s no way to know which screen a given unit will come with, and no way to calibrate the color balance to personal preferences. Each screen has roughly the same top brightness level as the iPad 2.

It should be mentioned that the improved color saturation is far less noticeable when the new iPad and earlier iPads are set at 50% of their brightness, the level that Apple traditionally uses for testing of iPad batteries, and the one we’ve kept our iPads at in the past. At that level, the differences in vibrance become subtle. If you want to get the most out of the new iPad’s screen for photo editing, you’ll want to turn it up to 85% or higher brightness, and suffer increased battery drain as a result.

The two biggest remaining issues with the screen are the “fingerprint-resistant oleophobic coating” and the visibility outdoors in bright sunlight. Apple’s glass remains a fingerprint magnet, and our test units were literally covered in movie-obscuring smudges within hours—oil buildup that we find intolerable by the end of a day, and gross soon thereafter. Additionally, though the new iPad’s screen can be viewed on all the same crazy angles as its predecessors, no improvements have been made to aid the screen’s usability outdoors, where glare from the glass and bright sunlight demand higher than 50% brightness levels for optimal visibility. As was the case with past iPads, users should expect to wipe down the screen frequently, or choose fingerprint- and glare-resistant screen-covering film to dramatically mitigate these issues. See the Accessories section of this review for additional comments on that subject.

Another surprise concerns the chips Apple chose to include in the new iPad. Rather than radically departing from the A5 processor found in the iPad 2, Apple largely carried it over to this model, naming its new chip “A5X.” Notably, the company describes the new iPad as having “quad-core graphics” but not a quad-core CPU, which is accurate because Apple has kept the same 1 GHz ARM Cortex-A9 dual-core processor, augmenting it with a four-core Power VR SGX543MP4. This is the same graphics processor as the iPad 2, only with twice the processing cores, and 1GB of RAM rather than the previous 512MB. (For those keeping count, these specifications place the third-generation iPad in the same ballpark as Sony’s PlayStation Vita handheld game console, with a nearly identical CPU and GPU, more RAM, and a higher-resolution display, but half the CPU cores.)

While all of these numbers and letters can easily become confusing, the key things you need to know are as follows. Higher-resolution screens require more RAM and more powerful graphics chips just to keep up with the work of updating all the additional pixels. Since the third-generation iPad has four times the pixels of the prior models, one might imagine that it needs four times the RAM and four times the graphics processing power in order for its visuals to remain as fluid at the higher resolution. However, that’s not actually the case, so long as the prior-generation model was designed with more RAM and GPU power than its screen needed. The original iPad’s screen had no problems with 256MB of RAM or a considerably less powerful, single-core PowerVR SGX535. This iPad has four times the RAM and four times the GPU cores of the original model, with faster RAM and more capable cores.

Comparative testing with unoptimized GLBenchmark 1.1.7 benchmarking software suggests that the new iPad enjoys 1.5- to 1.9-billion texel per second fill rates, versus 0.91- to 0.97-billion texels on the iPad 2, with superior lighting capabilities when dealing with more on-screen objects. Almost everything else has remained roughly the same. GLBenchmark rates the new iPad’s CPU at 14815 in floating point math performance, versus 13333 for the iPad 2, with nearly identical integer performance at 18467 versus 18198 points. In other words, the new iPad has seen its textured pixel fill rate roughly double, with a tiny bump in CPU power for some math, but it’s otherwise mostly the same in horsepower. On paper.

Early real-world testing bears this out: the third-generation iPad feels almost precisely like the second-generation iPad in app loading and running speeds, except that the screen is capable of quietly performing considerably superior levels of detail for everything. Initial games and apps that have been updated to support the new iPad have the same frame rates, transitions, and smoothness they enjoyed on the iPad 2, but with higher resolutions. It remains to be seen what developers will be able to achieve after months of optimization, but we’re guessing that detail will be the major difference between generations.

Editors' Note: iLounge only reviews products in "final" form, but many companies now change their offerings - sometimes several times - after our reviews have been published.
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